Daikin R71FUV1 Service Manual page 486

Troubleshooting by Remote Controller
Cooling
High pressure
Low pressure
Suction
superheat
degree
Compressor
frequency
In response to decreased evaporator capacity
caused by refrigerant shortage, capacity is controlled
in the inverter in order to maintain a low pressure,
which resulting in a decrease in frequency.
Electronic
expansion
valve
Adequate
level
As compressor frequency
decreases, high pressure
decreases.
(Maintains a certain level
of low pressure)
As the electronic expansion valve
opening degree reaches the maximum,
suction superheated degree increases.
The maximum opening degree of the
electronic expansion valve (480 pulses)
Avoid overheat operation by
changing SC target value
(Degree of inadequate refrigerant)
Refrigerant shortage warning
Controlled high pressure
Actual high pressure
When frequency drops to the
lowest, it is impossible to
maintain a low pressure.
Reaches the lowest frequency
Si20-701_B
Abnormal refri g erant shortage
Inadequate
479